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Bloxiverz Side Effects

Generic Name: neostigmine

Note: This page contains information about the side effects of neostigmine. Some of the dosage forms included on this document may not apply to the brand name Bloxiverz.

For the Consumer

Applies to neostigmine: oral tablet

In addition to its needed effects, some unwanted effects may be caused by neostigmine (the active ingredient contained in Bloxiverz). In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking neostigmine:

More common:
  • Twitches of the muscle visible under the skin
Incidence not known:
  • Blurred or loss of vision
  • changes in patterns and rhythms of speech
  • chest pain or discomfort
  • confusion
  • cough
  • difficult or labored breathing
  • difficulty in moving
  • difficulty swallowing
  • disturbed color perception
  • dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
  • double vision
  • fast, pounding, or irregular heartbeat or pulse
  • halos around lights
  • hives
  • irregular, fast or slow, or shallow breathing
  • itching
  • lightheadedness, dizziness, or fainting
  • loss of consciousness
  • muscle cramps and spasms
  • muscle pain or stiffness
  • night blindness
  • no blood pressure or pulse
  • noisy breathing
  • overbright appearance of lights
  • pain in joints
  • pale or blue lips, fingernails, or skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • seizures
  • shortness of breath
  • skin rash
  • slow or irregular heartbeat
  • slurred speech
  • stopping of heart
  • sweating
  • tightness in chest
  • trouble in speaking
  • tunnel vision
  • unconsciousness
  • unusual tiredness or weakness
  • wheezing

If any of the following symptoms of overdose occur while taking neostigmine, get emergency help immediately:

Symptoms of overdose:
  • Constipation
  • decreased sexual ability
  • difficult urination
  • dry mouth
  • enlarged pupils
  • muscle weakness

Minor Side Effects

Some of the side effects that can occur with neostigmine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Increased watering of mouth
Incidence not known:
  • Bloated
  • constricted, pinpoint, or small pupils (black part of eye)
  • diarrhea
  • drowsiness
  • excess air or gas in stomach or intestines
  • feeling of warmth
  • full feeling
  • headache
  • increase in mucous from lungs
  • increased need to urinate
  • increased sweating
  • nausea
  • passing gas
  • passing urine more often
  • redness of skin
  • redness of the face, neck, arms and occasionally, upper chest
  • skin rash
  • stomach cramps
  • vomiting

For Healthcare Professionals

Applies to neostigmine: compounding powder, injectable solution, intravenous solution, oral tablet


The most common side effects included salivation, fasciculation, bowel cramps and diarrhea.[Ref]


Common (1% to 10%): Bradycardia, hypotension, tachycardia
Frequency not reported: Nonspecific EKG changes, cardiac arrest, syncope
Postmarketing reports: Cardiac arrhythmias (A-V block, nodal rhythm)[Ref]


Common (1% to 10%): Pruritus
Frequency not reported: Rash, urticaria[Ref]


Common (1% to 10%): Dry mouth, nausea (including post-procedural), vomiting
Frequency not reported: Flatulence, increased peristalsis
Postmarketing reports: Bowel cramps, diarrhea[Ref]


Frequency not reported: Urinary frequency[Ref]


Frequency not reported: Allergic reactions and anaphylaxis[Ref]


Frequency not reported: Muscle cramps and spasms, arthralgia
Postmarketing reports: Muscle weakness[Ref]

Nervous system

Common (1% to 10%): Dizziness, headache, postoperative shivering, prolonged neuromuscular blockade, insomnia
Postmarketing reports: Convulsions, drowsiness, dysarthria, fasciculation, loss of consciousness[Ref]


Frequency not reported: Miosis, visual changes[Ref]


Common (1% to 10%): Incision site complication, procedural complication and pain
Frequency not reported: Diaphoresis, flushing, weakness[Ref]


Postmarketing reports: Urinary frequency[Ref]


Common (1% to 10%): Pharyngolaryngeal pain, dyspnea, oxygen desaturation (less than 90%)
Frequency not reported: Increased oral, pharyngeal and bronchial secretions, dyspnea, respiratory depression, respiratory arrest, bronchospasm[Ref]


1. "Product Information. Bloxiverz (neostigmine)." Eclat Pharmaceuticals, Menomonee Falls,, WI.

2. "Product Information. Prostigman (neostigmine)." ICN Pharmaceuticals Inc, Cost Mesa, CA.

Not all side effects for Bloxiverz may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.